The Impact of Digitization on Green Innovation Performance: Evidence Based on Panel Data of 228 Prefectural-Level Cities in China

Table 1

Digitalization level indicator measurements.

Secondary indicators	Tertiary indicators
Digital foundation	Length of fiber optic cable per 10,000 square kilometres per 10,000 population
	Per capita long-distance telephone exchange capacity
	Local telephone capacity per capita
	Mobile phone switching capacity per capita
	Five three-level indicators of per capita Internet broadband access ports
Digital application	Mobile phone penetration
	Internet penetration
	Per capita landline subscribers
Digital development	The proportion of digital industry personnel
	Digital industry revenue share
	The proportion of fixed assets in the digital industry